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The dispersion stability and wettability of suspension concentrates are beneficial for improvement of the utilization rate of pesticides. Herein, four kinds of novel organosilane-modified polycarboxylate dispersants P(AA3-APEG1-Six) with different silicone contents ranging from 0 to 0.5 mol were successfully synthesized using acrylic acid (AA), allyl polyethoxyether (APEG-1000) and organosilicon modifier 3-(trimethoxysilyl)propylmethacrylate (MAPTMS) as monomers, and their surface properties were systematically investigated. Meanwhile, 25% tebuconazole (TEB) suspension concentrate (SC) was milled with the four P(AA3-APEG1-Six (SCP(AA3-APEG1-Six)), and the influences of P(AA3-APEG1-Six) on the zeta potential, particle size, suspension rate and rheological behaviors of the 25% TEB SC were also studied. The results showed that P(AA3-APEG1-Si0.5) had the lowest surface tension by maintaining an AA:APEG-1000 mole ratio of 3 : 1, and changing the MAPTMS additive amount from 0 to 0.5 mol. Additionally, the obtained TEB SCP(AA3-APEG1-Six) system exhibits shear thinning behavior under high shearing rate, showing typical features of a pseudo-plastic non-Newtonian fluid, which conforms to the Power-law model. More importantly, the SCP(AA3-APEG1-Six), especially for P(AA3-APEG1-Si0.5), exhibited relatively minimum change in particle size and zeta potential compared to that of the unmodified polymers, and displayed superior suspension rate. Significantly, TEB SCP(AA3-APEG1-Six) showed excellent wetting and spreading behavior on plant leaves, which contributes to obviously improving pesticide utilization.

This paper studies the impact of the R&D offshoring of multinational enterprises on the firms in host emerging economies. We develop a two-stage non-cooperative game to analyze the strategic interaction between multinational and host country enterprises engaged in R&D investment. An empirical analysis of 12,309 manufacturing firms in the ICT industry in China shows that R&D offshoring has a positive effect on the intensity of the R&D of host country firms. However, the magnitude of the impact depends on both the technological and geographical distance between the multinational and host country firms. The policy implications of these findings are that the governments of host country should be cautious about allowing advanced multinational R&D investment in under-developed sectors, but they should encourage such investment in developed sectors; and that local governments should be involved in R&D policy making because the positive impact of multinational R&D offshoring diminishes as the geographical distance between the multinational and host country firms increases.

选取55Bi2O3-25B2O3-10SiO2-7Ga2O3-3Yb2O3系统铋酸盐玻璃，研究了在不同温度（9～350K）下Yb^3^＋离子的发射光谱和荧光寿命变化情况，计算了不同温度下Yb^3^＋离子在976和1020nm的有效线宽△λeff,比较了不同温度下Ybb^3^＋离子的光谱特性和荧光寿命变化情况。发现随着测试温度的降低，测得的荧光寿命值以及荧光光谱半峰全宽（FWHM）和1020nm处的有效线宽△λeff却在增加。结果表明，在100K温度以下时，Yb离子在铋酸盐玻璃中下能级的粒子主要集中于最低能级上，使得Yb离子的运转状态由准三能级系统变为四能级系统。